Hydrothermal synthesis of Mo-V mixed oxides possessing several crystalline phases and their performance in the catalytic oxydehydration of glycerol to acrylic acid

Autor(es)

Rasteiro, Leticia F. ; Vieira, Luiz H. ; Possato, Luiz G. ; Pulcinelli, Sandra H. ; Santilli, Celso V. ; Martins, Leandro

• Tipo de documento: Artigo Científico
• Fonte: CATALYSIS TODAY; v. 296, p. 9-pg., 2017-11-01.

Resumo

The one-step oxydehydration of glycerol to acrylic acid over molybdenum and vanadium mixed oxides was investigated. The Mo-V oxide catalysts were prepared by a simple hydrothermal method under different synthesis and calcination atmospheres and were characterized by in situ XRD, TPD-NH3, N-2 adsorption/desorption, X-ray absorption near vanadium K-edge spectroscopy and thermogravimetry. The catalytic performance of the samples at different temperatures (290, 320 and 350 degrees C) and under different gas flow compositions (20% O-2 in N-2, 100% O-2, or 100% N-2) revealed that the arrangement of the crystallographic structures of the active phases directly influenced the catalytic performance. It was found that the catalysts heat-treated in oxidizing atmosphere gave superior catalytic results comparing with the catalysts heat-treated in inert atmosphere due to the equilibrium between the crystalline phases MoVO5 and Mo4.65V0.35O14 that contains V+4 and V+5. Catalytic oxydehydration at 320 degrees C under a flow of 100% O-2 gave the best performance, achieving selectivity of 33.5% towards acrylic acid and 100% conversion of glycerol. (AU)

• Processo FAPESP: 14/20116-6 - Desenvolvimento e aplicação de vanadossilicatos lamelares como catalisadores na desidratação oxidativa do glicerol
• Beneficiário: Luiz Henrique Vieira
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 16/10597-2 - Transformação catalítica do glicerol a partir de reações de desidratação e oxidação acopladas com o uso de catalisadores heterogêneos multifuncionais
• Beneficiário: Leandro Pierroni Martins
• Modalidade de apoio: Auxílio à Pesquisa - Regular